by Julie Cornelius, MS


Last week, I wrote a blog post about why I don’t think Ketogenic Diets are healthy. We got some responses from people who have had results on the diet and feel strongly about it. I wanted to take the time to respond to some of the comments to further explain my position. It is my opinion as a nutrition professional that the Ketogenic Diet is a fad diet. I know I will get a lot of criticism for saying that, but my views on nutrition do come from a skeptical scientific view where I delve into the research. I don’t claim that I know everything there is to know, but my views on nutrition come from years of studying the field throughout my education, years of keeping up on the latest research and years of working with individuals to help them with their nutrition. I don’t expect everyone to agree with everything I say or recommend. I will say that even if something is based on research, it does not mean that research is good. It does not mean that they did receive funding from an industry that wants to see a specific result. Nutrition is a relatively new science, which means that we really don’t know everything there is to know about it yet. That makes it both exciting because we are learning so much  new information, and also frustrating because we might not know exactly what foods or way of eating is the healthiest. I think a few things most everyone can agree on- fruits and vegetables are good for us and we need to get enough of certain nutrients in order to survive. So here are the questions I got and my response. I always welcome differing opinions, so keep the dialogue coming!


Comments to my original post:


I have switched to a ketogenic diet for performance I have have experienced none of the negative side effects that you talk about. I have lost 26 pounds, and my endurance, times, muscle mass and digestion have all improved. 

My response: There is plenty of research that does show a ketogenic diet helps to suppress appetite and can lead to weight loss: The research is still out if this weight loss can effectively and safely be maintained.

A low carb diet has plenty of fiber in the form of leafy green vegetables

That the ketogenic diet includes vegetables and fruits. They are included daily.


My response: Yes, eating plenty of vegetables can help to ensure someone gets enough fiber. Many people that I have talked to who follow a ketogenic diet do not consume very many vegetables, so I should have more specifically addressed this in my article. Most websites that advocate for a Ketogenic diet recommend lower than 20g of carbohydrates per day. This would not include a large amount of fruits and vegetables.

As for free radicals, there are whole cultures in history that never ate vegetables and didn’t have a problem with modern diseases of today.

My response: One problem with only looking at anecdotal evidence from past cultures, though, is that it does not address the problem that our modern society is bombarded with chemicals that contribute to free radical damage in the body. It is an unfortunate side effect of our evolution and technology.

Last but not least, you do not need glycogen stores if you are running on ketones.  I have ridden my bike for over five hours with only salt and water and have done just fine.


My response: I am very interested to hopefully see more research come out about ketogenic diets, but at this point, there is not much peer reviewed research that shows if they are beneficial or not:
The fat adaptation study is compelling, but at this point, it is one study that is not peer reviewed (published in a scientific journal that has been reviewed by other researchers in the field). I hope more research groups conduct similar studies to determine if ketogenic diets are safe in the long term. Some research I have looked at suggests that they may not be good for long term use, so at this point, I am very skeptical.


Julie CornelIMG_1601ius, MS is Co-founder of Potential Energy Training & Nutrition. She has an extensive background in nutrition and graduated from the University of Arizona in Tucson, AZ with both her Bachelors of Science and Masters of Science in Nutrition.  She has worked in fitness studios helping clients achieve their nutrition goals, spent two years teaching college nutrition courses, and was the founder of Julie Bar, an energy bar company. Julie is a long time cyclist and mountain biker who loves being outdoors. Julie helps individuals to meet their nutrition goals, whether it is eating to win an endurance mountain bike race, losing weight, or just eating to be healthier. Connect with Julie:

Response to Last Week’s Blog About Ketogenic Diets